Tubing hanger assembly and method of using same for hanging tubing in a well under pressure with no check valve in tubing

ABSTRACT

A tubing hanger assembly and method of using same for hanging tubing in a well under pressure, wherein the tubing has no check valve therewith. The assembly includes means for sealing off around the tubing, supporting the tubing, cutting the tubing after so sealed and supported, shutting off flow through the tubing above the portion of the tubing remaining in the well after cutting it off, so that the wellhead equipment above the tubing hanger may be removed while leaving the tubing available for injecting chemicals into the well and for performing similar well operations.

United States Patent [151 3,692,107 Slator et al. [4 1 Sept. 19, 1972 [s41 TUBING HANGER ASSEMBLY AND 2,969,838 l/1961 Wilde ..l66/55 METHOD OF USING SAME FOR 3,379,255 4/1968 Burns 6123.1 ..166/55 HANGING TUBING IN A WELL UNDER 3,399,728 9/1968 Taylor ..25 1/1 X PRESSURE WITH N CHECK VALVE 3,416,767 12/1968 Blagg .251/1 1N TUBING 3,561,526 2/1971 Williams ..l66/55 [72] Inventors: Damon T. Slator; Archie W. Peil,

both of Houston, Tex.

[73] Assignee: Bowen Tools, Inc. [22] Filed: Feb. 23, 1971 [21] Appl. No.: 117,946

[52] U.S. Cl ..166/55, 166/298 [51] Int. Cl. ..E2lb 29/00 [58] Field of Search 166/55, 298, 297, 75; 251/1 [56] References Cited UNITED STATES PATENTS 1,851,894 3/1932 Clough ..l66/55 2,840,166 6/1958 Eckelet al ..166/55 2,919,111 12/1959 Nicolson ..25l/1 X f r 2; a l

Primary Examiner -David H. Brown Attorney-Pravel, Wilson & Matthews [5 7] ABSTRACT after cutting it off, so that the wellhead equipment above the tubing hanger may be removed while leaving the tubing available for injecting chemicals into the well and for performing similar well operations.

6 Claims, 7 Drawing Figures PATENTEIJsms um 3.692.107

sum 3 or 3 plume! MAW & MaHLewA v ATTORNEYS TUBING HANGER ASSEMBLY AND METHOD OF USING SAME FOR HANGING TUBING IN A WELL UNDER PRESSURE WITH NO CHECK VALVE IN TUBING BACKGROUND OF THE INVENTION The field of this invention is tubing hanger assemblies and methods of using same.

In recent years, tubing in continuous lengths without joints or collars has been introduced into wells through the usual well head equipment, an example of which is illustrated in U.S. Pat. No. 3,313,346. So longas the wellhead equipment is in place, the tubing may be used for performing various operations such as the injection of gas to stimulate the flow of oilfrom a well and the injection of paraffin solvents and other chemicals. If only one ormore of such operations is to be performed, the

tubing and the wellhead equipment can simply be removed after the operation, but in some instances, periodic operations on a weekly or monthly basis are required, and it is therefore desirable to have the tubing in the well, but the wellhead equipment and injection apparatus are too expensive to leave in an idle condition for such extended periods between the operations.

SUMMARY OF THE INVENTION .The present invention relates to a new and improved tubing hanger assembly and method of using same in a well under pressure, wherein the tubing has no check valve therewith. When it is desired to remove the wellhead equipment, the tubing is sealed off and supported by the hanger assembly. Then, the tubing is cut inside of the hanger assembly and a shut-off valve is closed to control well pressure. Thereafter, the wellhead equipment may be removed and periodic injections through the tubing may still be accomplished, preferably using a cap and valve at the upper end of the hanger assembly.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is an elevation of the apparatus of this invention in position during the injecting of tubing into a well casing;

FIG. 2 is a vertical sectional view, partly in elevation, of the tubing hanger assembly of this invention prior to the disconnection of the wellhead equipment therefrom;

FIG. 3 is a vertical sectional view of a portion of the tubing hanger assembly of FIG. 2, illustrating the tubing after it has been severed and the shut-off means has been closed, and the wellhead equipment has been removed from the tubing hanger assembly;

FIG. 4 is a view similar to FIG. 3, but illustrating a typical control assembly, including an external valve, located on the body of the tubing hanger assembly after the wellhead equipment has been removed from the tubing hanger assembly;

FIG. 5 is an enlarged vertical sectional view, partly in elevation, illustrating the lower portion of the tubing hanger assembly illustrated in FIG. 2, showing in detail the preferred supporting means and sealing means prior to actuationthereof into supporting and sealing positions;

FIG. 6 is a view similar to FIG. 5, but showing the supporting means in gripping engagement with the tubing for supporting same, and the sealing means in sea]- ing contact with the external surface of the tubing; and

FIG. 7 is a cross-sectional view taken on line 7--7 of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, the letter T designates generally the tubing hanger assembly of this invention which is adapted to be positioned above a well casing C (FIG. 1)

and below conventional wellhead equipment W. The

, as the injector apparatus A schematically indicated in FIG. I, a detailed example of which is disclosed in U. S. Pat. No. 3,285,485. Briefly, the present invention re lates to the tubing hanger assembly T and the method of using same under conditions wherein the well is under pressure, and the tubing P does not have a check valve or other means for controlling fluid flow through the tubing therewith. The tubing hanger assembly T, as will be explained in detail, includes a structure which makes it possible to support and seal off the tubing within the tubing hanger assembly T and also to cut the tubing and control the fluid flow therethrough to enable the wellhead equipment W thereabove to be removed.

Considering the invention more in detail, the tubing hanger assembly T includes a body B which is formed of a plurality, of parts with a longitudinal bore therethrough, which the tubing P is adapted to extend (FIG. 2). As illustrated in particular in FIG. 2 of the drawings, the body B includes body sections 10 and 11 which are joined by a cylindrical expander actuator section 12, the purpose of which is to be hereinafter explained. Also, the body B includes a housing section 14 for a cutter means K, and which has a housing exten- Sion 14a for retaining a shut-off means S, as will be more fully explained. The upper end of the housing extension l4a has external threads 14b or other suitable means for connecting to the lower end of an adapter or pipe 15 (FIG. 2) which is at the lower end of the wellhead equipment W (FIG. I

The expander actuator 12 has upper internal threads which are in threaded engagement with external threads 10a at the lower end of the body section 10 so that upon rotation of the actuator 12, it moves downwardly relative to the body section 10. Also, the actuator 12 has lower internal threads 12b which are in threaded engagement with external threads 11a on the body section 11 so that as the threads 10a and 12a are unthreaded from each other, the threads 12b make up on the threads Ila, thereby keeping the body sections 10 and 11 connected with each other through the actuator 12 as the actuator 12 is rotated, as will be more evident hereinafter.

The body section II has lower external threads llb which are in threaded engagement with a casing flange 16 which is connected in any known or suitable manner to a flange on the casing C (FIGS. 1 and 2). The upper end of the body section 10 has external threads 10b which are used for threaded engagement with threads 14c formed internally of the cutter means housing 14 so that such housing 14 forms a continuation of the body section 10.

As best seen in FIGS. 2, 5 and 6, the body section preferably has an annular shoulder 10d which serves as a support for a pair of support members 20, each of which is preferably semi-cylindrical and is formed with gripping teeth a on a curved surface which has a radius conforming with the radius of the tubing P so that when the members 20 are moved inwardly into gripping engagement with the external surface of the tubing P, the teeth 20a engage and bite into the surface of the tubing P to facilitate the gripping action. The external surface 20b of each of the members 20 is preferably in engagement with the inner surface We of the body section 10 when the members 20 are in the retracted or open position (FIG. 5) out of contact with the pipe P.

Each of the members 20 is preferably formed with a dovetail slot 20c which receives a correspondingly tapered end 21a on an operating rod or screw 21. Such construction facilitates the assembly of the gripping members 20 on the operating rods 21 since the operating rod 21 may be positioned through the wall of the body section 10 and then the members 20 may be moved or dropped downwardly longitudinally with the tapered ends 21a in the slots 20d. After the rods 21 are thus assembled on the gripping members 20, radial or lateral movements of the rods 21 are thereafter transmitted to the members 20 for lateral movement of such members 20 inwardly to grip the tubing P, or outwardly to release such gripping action.

Although the operating rods 20 may be mounted directly through the wall of the body section 10, they are preferably threaded into a fixed insert 23 which is threaded or is otherwise secured through the wall of the body section 10. The insert 23 has internal threads 23a which co-act with external threads 21b on each operating rod 21, so that upon rotation of each rod 21, it

moves its respective gripping member 20 inwardly and outwardly, depending upon the direction of rotation of the rods 21. A stop nut 24 is secured to each operating rod 21 inwardly of wrench flats 210, which stop nut 24 serves to limit the inward travel of the rod 21. Suitable O-rings 25 and 26 are provided to prevent the escape of fluid around the operating rod 21 and the insert 23.

The gripping members 20 are retained in the body section 10, in a seated position on the annular shoulder 10d by an annular retaining ring 27 (FIGS. 5 and 6) which is held in place by a snap ring 28 or other suitable means fitting into a groove 10f in the body section 10. Since the snap ring 28 or any other suitable attaching means is removable, the ring 28 is therefore removable, thereby permitting the removal of the gripping members 20 from the body section 10, if desired. Also, it will be appreciated that such construction facilitates the assembly of the tubing supporting means as heretofore described.

The body section 11 has a counterbore 11c, forming an annular lateral shoulder 11d for receiving a resilient packing element 30 formed of rubber or other suitable resilient material. The external circumferential surface 30a of the packing element 30 is in engagement with the bore 11c while the inner surface 30b of the packing element 30 is of a diameter which is approximately the same as the longitudinal bore of the rest of the body such as the body sections 10 and 11, so as to normally be out of contact with the external surface of the tubing P (FIGS. 2 and 5).

A packing expander sleeve 32 is formed of steel or other similar relatively hard material and it is disposed above the packing member 30 for longitudinal movement within the bore of the body section 11 for laterally distorting and compressing the packing member 30 to form a seal between the inner surface 30b and the external surface of the tubing T. To facilitate such lateral distortion of the packing member 30 by the longitudinal downward movement of the expander sleeve 32, the sleeve 32 preferably has a downwardly and outwardly tapered lowered surface 32a which engages a correspondingly inclined or tapered upper surface 300 on the packing member 30. The inside diameter 32b of the sleeve 32 is preferably of the same diameter as the inside bore 30b of the packing element 30 when the element 30 is in its normal undistorted condition (FIG. 5).

An external shoulder 320 is formed in the expander sleeve 32 for receiving an inwardly extending shoulder 12c on the expander actuator 12 so that downward movement of the actuator 12 are transmitted to the expander sleeve 32. Suitable O-rings 33 and 34, or other sealing means, formed of rubber or other suitable sealing material, are preferably provided to seal off the threads above and below such seals from the fluid which may be inside of the tubing hanger assembly. The actuator 12 may be rotated in any suitable manner, but as illustrated in the drawings, spanner wrench holes 12d are preferably provided in the external surface thereof for engagement by a conventional spanner wrench in the known manner for imparting rotation to the actuator 12 relative to the sections 10 and 11.

The knife means or cutter means K, which is illustrated in particular in FIGS. 2-4, includes a lower cutter blade 40 and an upper cutter blade 41. The lower cutter blade 40 is mounted on a slidable support 40a having a bore 40b of a diameter sufficient to permit lateral shifting of the support 400 and the blade 40 therewith, as will be more evident hereinafter. The upper cutter blade 41 is mounted on a laterally movable support 41a which has a longitudinal bore 41b which also has a diameter large enough to permit lateral shifting or movement of the blade 41 for cutting action to sever the pipe P. An operating handle 400 is connected with the lower blade support 40a, and a similar operating handle 41c is connected to the support 41a for the upper cutter blade 41. The two operating handles 40c and 410 are preferably pivotally connected to a common handle 42 as illustrated in FIG. 1, in any conventional manner so that the operating handles or rods 40c and 410 are moved simultaneously in opposite directions to thereby move the cutter blades 40 and 41 towards each other for cutting action to sever the tubing P, as can be seen from a comparison of the positions of the cutter blades 40 and 41 in FIGS. 2 and 3. Instead of such knife means K shown in the drawings, a standard cutting means mounted on blowout preventer rams may be used for cutting the tubing P.

The shut-off means S is any type of valve through which the tubing P can pass and which can completely close off when the tubing P is out of the valve. By way of example, the valve illustrated has a valve seat 45 which is disposed in the housing extension 14a and which receives a ball 46'which is rotatably mounted therein. A valve flow passage 46a through the ball 46 is adapted to be moved from a closed position (FIG. 3) to an open position (FIG. 2), and vice versa, by any suitable control preferably extending externally of the housing extension 14a as indicated schematically at 46b (FIG.1). The valve seat 45 and therefore the ball valve 46 itself is retained in the housing extension 14a by a retaining sleeve 47 which is threaded oris otherwise secured in such extension 14a.

I A control assembly D, illustrated in particular in FIG. 4 is added after the wellhead assembly W has been removed, as will be more fully explained. Such control assembly D is constructed so that it fits with the housing extension 1421 and is preferably threaded onto the threads 14b by internal threads 50a on a retaining collar 50. The retaining collar 50 holds a closure cap 51 in seated position at the upper end of the housing extension 14a by the engagement of an annular shoulder 50a with an annular flange 51a on the cap 51. The flange 51a also preferably engages the upper edge 14 c of the housing section 14a when it is in the seated position. A pipe 52 having an external valve 53 is mounted with the cap 51 for controlling the inlet and outlet of fluid with respect to the tubing P after the wellhead assembly has been removed. Other suitable control equipment besides the valve 53 may of course be utilized, depending upon the particular operating conditions and the procedures involved. An O-ring 54 or other suitable sealing means is preferably provided between the cap 51 and the bore of the housing extension 14a (FIG. 4).

In carrying out the method of this invention, it will be understood that the tubing P is initially inserted with the injector apparatus A (FIG. 1) and the tubing P may be withdrawn and reinserted and otherwise used for a period of time prior to utilizing the method of the present invention. When it is desirable to remove the wellhead equipment W then the method of this invention is utilized.

Since the tubing P does not have a check valve or any means to control the fluid flow from the well therethrough, the apparatus of the present invention is utilized in carrying out the method so that the tubing P can be cut and the well can properly be maintained under control by means of the shut-off means S. Thus, in carrying out the method of this invention, the seal 30 is first brought into sealing contact with the external surface of the pipe P, while the pipe P is extending through the entire tubing hanger assembly T as shown in FIG. 2. This is accomplished by rotating the actuator 12 from the position shown in FIGS. 2 and 5 to a lower position such as that shown in FIG. 6, wherein the packing or sealing element 30 is compressed and is confined in sealing contact with the external surface of the pipe P so that no fluid can pass externally of the pipe P. Thereafter, the supporting means is actuated to move the gripping or supporting members 20 inwardly from the retracted or open position of FIGS. 2 and 5 to the supporting gripping position of FIG. 6. Such movement of the gripping members is accomplished by rotating the threaded rods 21 so as to cause the gripping members 20 to move inwardly.

With the tubing or pipe P thus sealed off externally and gripped externally so as to supportsame, the tubing P is cut by moving the cutter blades 40 and 41 inwardly and relative to each other from the position shown in FIG. 2 to the position shown in FIG. 3.

After the tubing or pipeP is cut, the well is maintained under control while pulling the upper part of the tubing P above the cut-off means S upwardly because of a seal between such upper part of the tubing and a stuffing box 8' (FIG. 1) of conventional construction which seals around the tubing T. When the upper portion of the tubing P above the cutter means. K has moved above the shut-off means S, the shut-off means S is closed (FIG. 3) so that the well is under control without any need for the stuffing box S, and therefore, the wellhead equipment W may be removed from the housing extension 14a. Such removal leaves the threads 14b at the upper end of the tubing hanger assembly T exposed as shown in FIG. 3, so that subsequently the control assembly D may be mounted on the housing extension 14a as shown in FIG; 4. The shut-off means S may then be opened to the position shown in FIG. 4 so that thereafter, the flow control to or from the tubing P may be regulated through the valve 53 which is located externally of the tubing hanger assembly T. The shutoff valve S may of course be closed again if desired.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials as well as in the details of the illustrated construction may be made without departing from the spirit of the invention.

We claim:

I. A tubing hanger assembly, comprising:

a body adapted to be mounted at a wellhead below wellhead equipment and having a longitudinal bore through which tubing is adapted toextend; tubing supporting means in said bore normally disposed out of contact with saidtubing but .being movable laterally into supporting engagement with said tubing;

sealing means in said bore normally out of contact with said tubing but movable into sealing engagement therewith;

cutter means in said bore normally disposed out of contact with said tubing but being movable for cutting off the portion of said tubing above said cutter means; and

shut-off means connected above said cutter means and having an opening therethrough through which the tubing extends when said shut-off means is in the open position, and being movable to a closed position after the cut off portion of said tubing above said cutter. means is removed from said body.

2. The structure set forth in claim 1, including:

a control assembly adapted to be connected to the upper end of said body for closing the upper end thereof after said cut-off portion of said tubing has been removed.

3. The structure set forth in claim I, wherein said cutter means includes:

a lower cutter blade having means mounting same for lateral movement in said body from an open position out of contact with said tubing to a cutting position;

an upper cutter blade having means mounting same each of said supporting means, sealing means, cutter above Said lower cutter blade in Said body f means and shut-off means has means therewith for lateral P an P p out of operating each of said means from externally of contact with said tubing to a cutting pos1t1on;and id b d means for moving said cutter blades relative to each 5 The Structure set f th in claim 1 wherein Said other to effect said cutting off of the portion of the body includes:

tubing thereabove. a first tubular bod y section, 4. The structure set forth m claim 1, wherein said asecond tubular body sectiomand shut'offmeansmchldesl an expander actuator sleeve threaded to said body a valve rotatable in said body from said open position 10 sections for oining them together and for longituto said closed position; and means mounting Said valve in Said body above said dmal movement of said actuator sleeve relative to said body sections.

cutter means. 5. The structure set forth in claim 1, wherein: 

1. A tubing hanger assembly, comprising: a body adapted to be mounted at a wellHead below wellhead equipment and having a longitudinal bore through which tubing is adapted to extend; tubing supporting means in said bore normally disposed out of contact with said tubing but being movable laterally into supporting engagement with said tubing; sealing means in said bore normally out of contact with said tubing but movable into sealing engagement therewith; cutter means in said bore normally disposed out of contact with said tubing but being movable for cutting off the portion of said tubing above said cutter means; and shut-off means connected above said cutter means and having an opening therethrough through which the tubing extends when said shut-off means is in the open position, and being movable to a closed position after the cut off portion of said tubing above said cutter means is removed from said body.
 2. The structure set forth in claim 1, including: a control assembly adapted to be connected to the upper end of said body for closing the upper end thereof after said cut-off portion of said tubing has been removed.
 3. The structure set forth in claim 1, wherein said cutter means includes: a lower cutter blade having means mounting same for lateral movement in said body from an open position out of contact with said tubing to a cutting position; an upper cutter blade having means mounting same above said lower cutter blade in said body for lateral movement from an open position out of contact with said tubing to a cutting position; and means for moving said cutter blades relative to each other to effect said cutting off of the portion of the tubing thereabove.
 4. The structure set forth in claim 1, wherein said shut-off means includes: a valve rotatable in said body from said open position to said closed position; and means mounting said valve in said body above said cutter means.
 5. The structure set forth in claim 1, wherein: each of said supporting means, sealing means, cutter means and shut-off means has means therewith for operating each of said means from externally of said body.
 6. The structure set forth in claim 1, wherein said body includes: a first tubular body section; a second tubular body section; and an expander actuator sleeve threaded to said body sections for joining them together and for longitudinal movement of said actuator sleeve relative to said body sections. 